-----Original Message----- From: dovecot-bounces@dovecot.org [mailto:dovecot- bounces@dovecot.org] On Behalf Of Simon Brereton

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-----Original Message----- From: Timo Sirainen [mailto:tss@iki.fi] On Fri, 2011-09-09 at 13:07 -0400, Simon Brereton wrote:

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I have a server that's been running Courier for about 6 years and in all that time I think I've only ever had 1 issues where an entire mail box was repopped by a webmail client. However, since moving to a new server and dovecot 4 weeks ago, I've now had the webmail client repop this account 4 times (there are about 230 mails in the account).

Is there a setting I need to tighten to prevent/remedy this? I have no idea if it's happening on other accounts, but this is one that I see. The format is maildir. There has been no changes to the webmail client.

dovecot -n output would have been nice. Also do you see anything in error logs?

Ah. My apologies of course. Here it is..

mail:~# dovecot -n # 1.2.15: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.2 ext3 log_timestamp: %Y-%m-%d %H:%M:%S protocols: imap imaps pop3 pop3s ssl_ca_file: /etc/ssl/keys/rhodes-ca.crt ssl_cert_file: /etc/ssl/keys/mail.domain.net.crt ssl_key_file: /etc/ssl/private/mail.domain.net.key disable_plaintext_auth: no login_dir: /var/run/dovecot/login login_executable(default): /usr/lib/dovecot/imap-login login_executable(imap): /usr/lib/dovecot/imap-login login_executable(pop3): /usr/lib/dovecot/pop3-login mail_privileged_group: mailsystem mail_location: maildir:/var/spool/mail/virtual/%d/%n maildir_very_dirty_syncs: yes mbox_write_locks: fcntl dotlock mail_executable(default): /usr/lib/dovecot/imap mail_executable(imap): /usr/lib/dovecot/imap mail_executable(pop3): /usr/lib/dovecot/pop3 mail_plugins(default): quota imap_quota mail_plugins(imap): quota imap_quota mail_plugins(pop3): quota mail_plugin_dir(default): /usr/lib/dovecot/modules/imap mail_plugin_dir(imap): /usr/lib/dovecot/modules/imap mail_plugin_dir(pop3): /usr/lib/dovecot/modules/pop3 imap_client_workarounds(default): outlook-idle delay-newmail imap_client_workarounds(imap): outlook-idle delay-newmail imap_client_workarounds(pop3): pop3_client_workarounds(default): pop3_client_workarounds(imap): pop3_client_workarounds(pop3): outlook-no-nuls oe-ns-eoh lda: postmaster_address: postmaster@domain.net mail_plugins: quota log_path: info_log_path: deliver_log_format: msgid=%m: %f: %$ auth default: mechanisms: plain login user: mailsystem verbose: yes passdb: driver: sql args: /etc/dovecot/dovecot-sql.conf userdb: driver: prefetch userdb: driver: static args: uid=999 gid=115 home=/var/spool/mail/virtual/%d/%n allow_all_users=yes socket: type: listen client: path: /var/spool/postfix/private/auth mode: 432 user: postfix group: mailsystem master: path: /var/run/dovecot/auth-master mode: 432 user: mailsystem group: mailsystem plugin: quota: maildir

Could you make dovecot -n munge the certificate and postmaster email addresses? I'm not comfortable with that floating on the internet..

The only thing I have in the logs is 2 sessions where mail was popped (note, it doesn't even add up to the 183 messages in the mail box). But those sessions are vastly longer than the regular ones (tens of minutes compared to a few seconds). Since both IPs are on the back- bone, that's quite a while to download 100 mails (none of which are over

Sep 11 21:36:25 mail dovecot: pop3-login: Login: user=<user@domain.com>, method=PLAIN, rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 11 21:36:34 mail dovecot: POP3(user@domain.com): Disconnected: Logged out top=0/0, retr=0/0, del=0/183, size=14025971 Sep 11 21:43:44 mail dovecot: pop3-login: Login: user=<user@domain.com>, method=PLAIN, rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 11 21:44:54 mail dovecot: POP3(user@domain.com): Disconnected: Logged out top=0/0, retr=0/0, del=0/183, size=14025971 Sep 11 21:52:31 mail dovecot: pop3-login: Login: user=<user@domain.com>, method=PLAIN, rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 11 22:56:01 mail dovecot: POP3(user@domain.com): Disconnected: Logged out top=0/0, retr=100/9182678, del=0/183, size=14025971 Sep 11 23:08:58 mail dovecot: pop3-login: Login: user=<user@domain.com>, method=PLAIN, rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 11 23:37:57 mail dovecot: POP3(user@domain.com): Disconnected: Logged out top=0/0, retr=75/4748674, del=0/183, size=14025971 Sep 12 00:04:11 mail dovecot: pop3-login: Login: user=<user@domain.com>, method=PLAIN, rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 12 00:04:26 mail dovecot: POP3(user@domain.com): Disconnected: Logged out top=0/0, retr=0/0, del=0/183, size=14025971 Sep 12 00:07:40 mail dovecot: pop3-login: Login: user=<user@domain.com>, method=PLAIN, rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 12 00:07:53 mail dovecot: POP3(user@domain.com): Disconnected: Logged out top=0/0, retr=0/0, del=0/183, size=14025971

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If you're using the default pop3_uidl_format it'll rely on IMAP UIDs to stay the same, and I guess it's possible that due to some other problem they change (that should be logged as an error/warning though).

You could try setting pop3_uidl_format=%f, but it will cause everyone to redownload mails. With newer Dovecot versions you could set pop3_save_uidl=yes and when you think everyone's downloaded mails once you can safely change the pop3_uidl_format.

Sorry, I'm very new to dovecot and I'm not sure I understand. I presume because neither of those keys are in the dovecot -n output that they are as the defaults, yes? The account is indeed accessed by IMAP as well (from a mobile device mostly), but I don't see anything fishy there either. How could I see if the IMAP UIDs have changed?

Sep 11 21:20:32 mail dovecot: IMAP(user@domain.com): Connection closed bytes=1095/8292

Sep 11 21:26:03 mail dovecot: imap-login: Login: user=<user@domain.com>, method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 11 22:11:20 mail dovecot: IMAP(user@domain.com): Disconnected for inactivity bytes=725/5638 Sep 11 22:17:10 mail dovecot: imap-login: Login: user=<user@domain.com>, method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 11 23:12:06 mail dovecot: IMAP(user@domain.com): Disconnected for inactivity bytes=1471/11025 Sep 11 23:23:22 mail dovecot: imap-login: Login: user=<user@domain.com>, method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 11 23:52:52 mail dovecot: IMAP(user@domain.com): Connection closed bytes=1841/13679 Sep 12 00:08:47 mail dovecot: imap-login: Login: user=<user@domain.com>, method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 12 01:19:05 mail dovecot: imap-login: Login: user=<user@domain.com>, method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 12 02:57:01 mail dovecot: IMAP(user@domain.com): Connection closed bytes=2713/60026 Sep 12 02:57:01 mail dovecot: IMAP(user@domain.com): Connection closed bytes=2688/18635

There are no errors or warnings in the mail log (I have one shared log file for postfix, amavis and dovecot). Reading the notes for pop3_save_uidl it doesn't seem to be a dangerous option - should I turn that on? Why will it force everyone to redownload mails (there's nothing about it on the wiki)?

Thanks!

Simon

Any help would be appreciated.

Thanks.

Simon